In recent years, a number of new service features have been provided by an enhanced telephone network, sometimes referred to as an Advanced Intelligent Network (AIN). In an AIN type system, local and/or toll offices of the public telephone network detect one of a number of call processing events identified as AIN "triggers". For ordinary telephone service calls, there would be no event to trigger AIN processing; and the local and toll office switches would function normally and process such calls without referring to the central database for instructions. An office which detects a trigger will suspend call processing, compile a call data message and forward that message via a common channel interoffice signalling (CCIS) link to an Integrated Service Control Point (ISCP) which includes a Multi-Services Application Platform (MSAP) database. If needed, the ISCP can instruct the central office to obtain and forward additional information. Once sufficient information about the call has reached the ISCP, the ISCP accesses its stored data tables in the MSAP database to translate the received message data into a call control message and returns the call control message to the office of the network via CCIS link. The network offices then use the call control message to complete the particular call.
An AIN type network for providing an Area Wide Centrex service was disclosed and described in detail in commonly assigned U.S. Pat. No. 5,247,571 to Kay et al., the disclosure of which is entirely incorporated herein by reference. AIN type processing in such a system is controlled by the ISCP, which typically is operated by the local exchange carrier.
Similar intelligent services, particularly advanced 800 number services, may be offered by other carriers using call processing methodologies similar to those used in AIN. Existing 800 number call processing utilizes a central 800 database in a Service Control Point (SCP), to control switching operations through multiple end offices. Local and/or toll offices of the network detect dialing of an 800 number, suspend call processing, compile a call data message and forward that message via a common channel interoffice signalling (CCIS) link to the 800 database in the SCP. The SCP accesses stored data tables identified by the dialed 800 number to translate the received message data into a call control message, including a plain old telephone service (POTS) type destination telephone number. In this system, if the SCP does not currently store the destination number corresponding to a particular 800 number, the SCP will obtain the destination number from a national 800 database referred to as a Service Management System (SMS). The SCP transmits the call control message to the office of the network via CCIS link, and the network offices use the POTS destination telephone number in the call control message to complete the particular call. Examples of 800 number call processing routines are disclosed in U.S. Pat. No. 4,191,860 to Weber, U.S. Pat. No. 4,611,094 to Asmuth et al. and U.S. Pat. No. 4,611,096 to Asmuth et al.
In AIN services, 800 number call processing and the like, one trigger always results in a query to one database which results in a response message to provide a selected feature as part of a unified service. Even where the network includes multiple databases, the customer cannot obtain independent services from separate providers off the same trigger, e.g. in response to all calls to the subscriber's one number. A number of examples of such unified processing are described in more detail below.
U.S. Pat. No. 5,136,636 to Wegrzynowicz discloses an enhanced 800 number system for selecting a local dealer from among a group of dealers for completion of each 800 number. When a caller dials an 800 number, the call is first connected to an originating screening office action control point (OSO-ACP) 110 of the toll switching system. The OSO-ACP launches a first query to an INWATS (800 number) database. The INWATS database translates the data in the initial query into an initial response message which includes a special routing number, i.e. including a three digit prefix such as 195, which can not be dialed as the first three digits of a valid telephone number. The OSO-ACP recognizes from the prefix digits that an additional query is necessary and launches a second query directed to one of a plurality of direct services dialing databases. The direct services dialing database which receives the second query uses the routing number to access a segment of data within the database to translate the caller's NPA plus office code into the POTS telephone number of a nearby dealer. The direct services dialing database transmits the POTS telephone number back to the OSO-ACP, and the OSO-ACP uses that number to complete the call.
U.S. Pat. No. 4,827,500 to Binkerd et al. discloses a system for providing a call distribution feature on 800 calls in response to either DTMF or speech input commands from the caller, using data from a basic 800 number database and an Advanced 800 number database. When a caller dials an 800 number, the call is routed to an originating screening office which transmits a first query to the 800 number database. If the file in the 800 number database indicates that Advanced 800 number processing in response to DTMF or speech inputs is necessary, the 800 number database returns a message to the originating screening office which includes a destination number corresponding to an Action Control Point (ACP) which is capable of processing the Advanced 800 number calls. The originating screening office switch uses the received number to route the call to the ACP, and in response, the ACP initiates a query message to the Advanced 800 number database asking how to route the present call. The Advanced 800 number database sends a message to the ACP instructing it to route the call to an announcement point, which has a voice processing unit associated therewith. The Advanced 800 number database also sends a message to the announcement point instructing it to play a specific message from the voice processing unit to the present caller and receive tone or speech command signals back from the caller. The voice processing unit derives data from the received signals, and the announcement point forwards that data to the Advanced 800 number database. The database uses the received data, together with the dialed number and the number of the caller, to derive a plain old telephone service type destination number from stored data. The Advanced 800 number database forwards the derived destination number back to the ACP. The ACP drops the connection to the announcement point and requests a connection through the public switched telephone network to the station identified by the destination number.
U.S. Pat. No. 4,924,510 to Le teaches provision of a dynamic table of the most frequently called Advanced 800 numbers and the corresponding routing data in each toll switching system. When a toll switching system receives an 800 call, the table is examined to see if the Advanced 800 service assessing data is stored. If so, the toll switching system accesses the Advanced 800 database directly without first accessing a Basic 800 database. If the data for accessing the Advanced 800 service is not stored in the toll switching system's table, the call is processed in a manner similar to that disclosed in the above discussed Binkerd et al. Patent. The toll switching system updates the table if the call was directed to an Advanced 800 customer.
U.S. Pat. No. 4,987,587 to Jolissaint pertains to method and apparatus for providing an 800 number customer an on-site customer-made determination of what further action should be taken in response to a caller dialing the customer's 800 number. The Jolissaint system includes apparatus for receiving from an 800 number network provider's Host Processor information expressive of an occurrence of a caller having dialed a customer's 800 telephone number. The information received by the customer's Host processor includes the dialed number and an identification of the caller's billing telephone number. The system includes an apparatus for determining at a customer's Host processor an action to be taken in response to the dialing of the 800 number. The customer's Hose processor may deny or accept the call or may route the call to an alternate destination, for example based on the caller's identity. The system further includes an apparatus for transmitting information as to what action the customer's host processor determined should be taken back to the network provider's Host Processor. The network provider's Host Processor then disposes of the call in the manner specified by the information from the customer's Host Processor. For example, if the call is to be accepted, the network provider's Host Processor forwards the call to the caller's local Host Processor.
In actual practice, 800 number services of the type discussed above are offered by multiple carriers, including local exchange carriers and interexchange carriers. When the NXX digits of the dialed 800 number identify an 800 number service offered by the local exchange carrier, the local exchange carriers' switch queries an SCP or ISCP operated by the local exchange carrier for the necessary call processing information. However, if the NXX digits of the dialed 800 number identify an 800 number service offered by a different carrier, the call goes to that carrier's point of presence (POP), and the query goes from the POP to that carrier's SCP. As such, there has been limited capability for carriers other than the local exchange carrier to offer intelligent network type services, e.g. only on outgoing calls wherein the caller dialed a specific type number (e.g. an 800 number). In each case, the query always is forwarded to the one database set up to always control processing of the one customer's 800 number calls. The existing call processing systems and methodologies have not provided alternate carriers with equal access to the trigger functionality of the AIN, to offer their own range of intelligent network type services off of the various types of triggers that the local exchange carrier's intelligent network can recognize.
Some patents have suggested access to other database systems and/or ISCPs of other carriers, but these proposals have still provided at most a limited form of access to the AIN trigger functionality and have not permitted a subscriber to utilize multiple provider's services effectively. Two examples are discussed below.
U.S. Pat. No. 5,311,575 to Friedes et al. teaches providing a customer database, essentially as a customer controlled extension of a network database maintained by the network service carrier. During call processing, a switch (ACP) of the public network queries the carrier's database, and if necessary, the carrier's database obtains additional information from the customer's database. Customers having PBX type on-premises equipment communicate with the subscriber database via a separate status data network. All services are provided through one carrier.
Commonly assigned U.S. Pat. No. 5,353,331 to Emery et al. discloses an AIN based system for offering personal communications service (PCS). As the subscriber roams, the wireless handset periodically registers its location through a mobile switch or through a home land line base station, and this information is recorded in the ISCP for use in routing subsequent calls to the handset at its current location. Of particular note here, in a nationwide implementation of such a system, with multiple ISCP databases, the ISCP in a given region serves as a mediation point to obtain necessary information from switches and ISCPs in other regions. When a subscriber registers through a remote region, either automatically or by initiating an outgoing call, the ISCP in that region executes a validation routine with the ISCP in the subscriber's home region, to confirm that the subscriber is valid and obtain data relating to that subscriber's services. Subsequently, when the home region is processing a call to the subscriber's number, the ISCP in that region communicates with the ISCP in the remote region to obtain information needed to route the call to the subscriber's current location. The switching systems in a particular region communicate with only the ISCP in the particular region. One function of the mediating ISCP is to process data from a distant ISCP to insure compatibility thereof with the switching systems in the particular region. The mediation function of the ISCP in the Emery et al. system, however, is still limited to only certain very specific trigger occurrences and provision of a single unified PCS service, albeit across geographic boundaries. The mediation occurs only in response to a need for validation of a roaming subscriber or in response to an incoming call. The distant carriers can not control the trigger responsive communication to provide a variety of different, independent services.
From the above discussion, it becomes clear that the existing systems and call processing functionalities provide alternate carriers at most a limited intelligent routing (using the carrier's own database) in response to only very specific limited triggering type events. Various carriers cannot use the same trigger to provide one subscriber a plurality of independent services. Alternate carriers have no access to most of the triggers used in AIN type processing, such as off-hook, off-hook delayed, etc. Consequently, such carriers can not provide intelligent network type services facilitated by such triggers unless the local exchange carrier first routes the call to a point of presence type switching system of the alternate carrier. Routing the voice call through the local network to an alternate carrier's switch, before triggering CCIS communication with the carrier's database utilizes an excessive amount of voice channel resources, for example if certain calls ultimately can not be completed. Also, such routing may necessitate double switching if the call needs to go back through the same local exchange carrier network to reach a particular destination.